Crankshaft grinder



May 16, 1944. w. H. MYERS GRANKSHAFI GRINDER Filed Feb. 25, 1941 3 Sheets-Sheet 2 INVENTOR ATTOR N E YS May 16, 1944. w. H. MYERS CRANKSHAFT GRINDER Filed Feb. 25, 1941 3 Sheets-Sheet 3 INVENTOR mym ATTOR N EYS Patented May 16, 1944 UNITED STATES FATENT OFFICE GRANKSHAFT GRINDER William Howard Myers, Glasgow, Mont. Application-FebruaryES, 1941, Serial No. 380,535

'9 Claims.

This invention relates to the art of grinding and truing cylindrical surfaces, andfhas among its' objects and advantages the provision of an improved crankshaft grinding apparatus.

In the accompanyingdrawings:

Figure l'is atop plan View ofthe invention illustrating a crankshaft mounted in the lathe for coaction with the device;

Figure 2 is a front elevational view of the structure illustrated in Figure 1;

Figure 3 is a side 'elevational viewwith certain partsbroken: away for the-sake of clearness;

Figure 4 isa sectional view along'the linedi of Figure 3;

Figure 5 is a sectional view along the lin 5- .5 of Figure3;

Figure 6 is a sectional 'view along the line 6-5 Figure 8 is a View taken substantially along the line 8-8 of Figure 3; and

Figure 9 is a view illustrating the device "in a position for grinding the main bearings of the crankshaft in contradistinction to its position in Figures '1 through 4 wherein one of the crank pins is being ground.

In the embodiment selectedto illustrate the'inventi'on, two parallel members 10 are arranged transversely of thelathe carriage l2 and fixedly related thereto by bolts 14. The carriage i2 is movable on the-ways It in the usual manner, which movement may be imparted thereto through the medium of the conventionalcarriage handle it associated with the lathe apronzil.

A- beam 22 is mounted above the members ill through the medium of links 24. -In Fig. 8, the lower ends of the links 24 areprovided-with bored heads 26 for the receptionoi a shaft 28 fixedly secured thereto by set screws 38. Bearings 32 are bolted to the members it! and rotatably support the ends of the shaft 28, the latter being provided with collars 34 engaging the respective bearings 32 to restrain the shaft from relative endWise movement. To the upper ends of the links 24 are fixedly connected pins 36 which are axially aligned in the direction of each other and mounted inbearings 3.8 bolted tothe channels 40 of the beam 22. Thus the beam 22 is pivotally mounted to the upper ends of the links 24, and the latter may pivot at their lower ends about the axis of the shaft 28. The grinding stone or disc 42 is mounted on the beam 22.

The channels m are spaced apart baclrto back and held in such spaced relation by spacer a l made secure by boltsdfi extending throughth'e respective spacers and channels. To the bottom flange'of each channel is bolted a bearing 48, see Fig.4, for supporting a shaft 455 to one end of which is fixedly 'connected'apulley 50. This pulley is driven by a belt 52 which in turn is driven by the pulley 54 operated by the motor 56 bolted to the cross members 58 bolted to the upper flanges of the channels 4!].

Figs. 1 and 2 illustrate the crankshaft 60 in position in the lathe, with one end of the cranishaft supported by the driving chuck 62 and the other end supported by the dead center 64. Obviously the axis of the main-bearings 6B coincides with the commonaxis of the chuck 62 and the dead center 64. Thus'the crank pins 68 rotate about the common axis of the lathe and the crankshaft when the latter is turned by the lathe. In grinding the crank pins 68, the beam 2-2 is'oscillated to move-the grinding stone 42 in a path conforming to the movement of the crank pin being ground. In Fig. 3, an arm 'Hl includes a right-angular projection 12 slidably guidedbetween walls 14 and spacers l6, withthe spacers and the walls secured into a unitary structure by bolts 13. Fig. Billustrates thebolts 18 as passing through the channels Ml, with the plates M fiting against the'backs of the channels so that the plates, the spacers and the channels are connected as a unitary structure, with the projection 12 adapted for longitudinal adjustment. Adjustment of the projection 12 is accomplished throughthe medium of a screw threaded into the bore 82. To the upper ends of the plates M is bolted a plate 84 bored to rotatably receive the unthreaded upper end of the screw 80. Relative longitudinal movement of the screw 8 is restrained by reason of a collar 86 secured to the screw and abutting one side of the plate 53 and a hand wheel 83 also fixed to the screw and abutting the opposite side of the plate. Thus rotation of the screw 80 imparts motion to the projection l2 which in turn moves the arm it! toward and away from the beam 22.

According to Fig. 3, the arm 10 is arranged at an angle of about 45 to the beam 22, which is also true of the projection 12. Thus the arm and its projection are so fashioned as to permit the grinding wheel to take a position partly inside the angle defined by the arm and its projection, with the three parts lying in a common plane. Such an arrangement permits the parts to be closely nested and conveniently arranged on a beam of relatively short dimension. The lower end of the arm 10 is fashioned with a short extent 99 which parallels the beam 22 and is notched to provide crank pin supporting surfaces 92 which are preferably arranged at right angles. This structure is best illustrated in Fig. 7, wherein the crank pin 93 is held against the faces 92 by a pin 94 slidable in a tubular member 96 located at the upper end of a bracket 98 bolted at I99 to the extension 99 of the arm I9. One end of a compression spring I92 engages the inner end of the pin 94 and its opposite end engages a plug I94 threaded into the tubular member. Adjustment of the plug I94 varies the tension of the spring I92 so that the pressure of the pin 94 against the crank pin 98 may be adjusted to suit different conditions.

One end of the plu is provided with a square opening for the reception of a key I96 which may be used for adjusting the plug. Contact between the end of the pin 94 and the crank 68 is located above the point of contact I 99 between the crank pin and the vertical surface 92 so that the crank pin is firmly held in position. In other words, the arm I9 is really tied to the crank pin 98, and the spring I92 permits the pin 94 to adjust itself to irregularities in the contour of the crank pin so that the two surfaces 92 are always held firmly against the peripheral face of the crank pin.

Since the crank pin 68 rotates about the axis of the crankshaft, the arm 19 is carried by the crank pin so that oscillatory motion is imparted to the beam 22 as well as to the links 24. Oscillatory motion of the beam 22 imparted thereto through the medium of the arm I9 which follows the crank pin 68, causes the stone 42 to follow the crank pin. Thus rotation of the crankshaft in the lathe presents all surfaces of the crank pin 98 to the stone. Precise adjustment of'the stone to the crank pin is accomplished through shifting of the arm I9 through rotation of the screw 89. The arm I9 may be adjusted to lower the extension 99 sufficiently far to permit the crank pin 68 to be placed between the grinding stone and the horizontal surface 92. The screw 89 is then adjusted to bring the crank pin I58 into engagement with the two surfaces 92 and the pin 94 is properly tensioned against the crank pin. While the beam 22 is pivotally mounted, the arm 79 is adjustably mounted thereto in such a manner as to permit the arm to be precisely positioned to the crank pin and the latter to the grinding stone. The beam 22 may be lowered to brin the grinding stone 42 into proper grinding relation with the crank pin 68 and the arm I9 then adjusted to precisely relate the faces 92 to the crankshaft, as illustrated in Fig. 3.

Figs. 1, 3 and 9 illustrate the motor 56. as being located near the end of the beam 22 opposite the grinding wheel 42, and the bearings 38 are located intermediate the ends of the beam to bring the weight of the motor to one side of the common axis of the bearings. Thus the motor counterbalances the beam in such manner as to tend to rotate the beam in a clockwise direction, as when viewingFigs. 3 and 9. Accordingly, the beam and grinding stone weight is held from the crank pin I58, and engagement between the crank pin and the grinding stone is accomplished bypivoting the beam downwardly to locate the grinding stone 42 in proper relation with the crank pin 98 and adjusting the arm 19 to lessen the distance between the axis of the ,pin 68 and the axis of the shaft 48. Under such conditions, the extension 99 is urged against the bottom side of the crank pin 98 in all positions of. the crank,

and the spring pressed pin 94 maintain the vertical surface 92 in firm engagement with the crank pin so that the beam 22, which carries the grinding stone 42, will oscillate strictl in accordance with the rotary motion of the crank pin 68.

Although the grinding stone 42 is illustrated as being considerabl narrower than the length of the crank pin 68, the stone is moved back and forth on the crank pin through manipulation of the carriage handle I9 through the medium of which the carriage, which carries the grinding mechanism, is moved back and forth on the ways For grinding purposes, it is essential that the grinding stone 42 be maintained in good condition and its peripheral surface concentric with the axis of the stone. To this end, Figs. 3, 5 and 9 illustrate a screw II9 provided with a diamond point H2 arranged to be moved into cutting engagement with the peripheral face of the stone through adjustment of the screw. The screw I I9 is threaded through a body I I4 slidable in a housing IIB bolted to a plate II8 secured to the bottom flanges of the channels 49 by bolts I29.

One side of the housing H6 is open and made closed by a plate I22 detachably secured to the housing by bolts I24. An adjusting screw I26 is threaded into the body I I4 and extends loosely through an opening in the end wall I28 of the housing for connection with a crank I39. Relative longitudinal movement of the screw I26 is restrained by reason of a flange I32 fixed to the screw and engaging one side of the end wall I28 and engagement of the crank hub I34 with the other side of the end wall. Since the body H4 is rectangular in cross section and fits snugly against the inner wall faces'of the housing IIG, rotation of the screw I26 through the medium of the crank I39 will shift the body II4 longitudinally of the housing for adjusting the screw II9 laterally of the grinding stone 42. Thus the screw IIII may be adjusted longitudinally for precisely position ing the cutting point II2 against the peripheral face of the grinding stone and lateral trim is accomplished through manipulation of the crank I39. Fig. 5 illustrates the plate I22 as being provided with a slot I36 of sufficient length to accommodate the necessary shift of the screw I I 9. r

The grinding device is fashioned to facilitate mounting thereof upon the carriage I2 of a lathe,

and the lathe is employed for imparting rotary motion to the crankshaft. Thus an ordinary lathe may be employed as a mount for the crank shaft as well as a source of power therefor. The oscillating action of the beam 22 permits the arm I9 to be effectively connected with the crank pin 68 to accurately follow the crank pin in its rotary travel. The cutting action of the grinding stone 42 is controlled through adjustment of the screw 89, and the screw is so angled as to conveniently position the hand wheel 89 directly before the operator at the lathe.

In Fig. 7, the gauge pin I38 of a surface dial gauge I49 is illustrated in engagement with the crank pin 68. The shank I42 of the dial gaugeis sufficiently far to bring the grinding stone 42 into alignment with the differentmain bearings or crank pin bearings. However, the crankshaft axis coincides with the common 'axisof the main bearingsso that the beam 22 action willbe somewhat different in that it' is devoid of any oscillatory action while operating on the'main bearings.

Fig. 9 illustrates thedevice adjusted-to work on the main bearing--66; To the rear-ends of'the members I are'bolted bearings I48 which rotatably support a shaft I50to which a brace arm I 52 is fixedly secured. A hook I54 is fashioned at the free end of the brace arm for-the reception of a bolt I56 threaded into one of thelinks 24. Normally the brace arm =I52hangs from the shaft I50. as in Fig. 3, but in grinding the main bearings, the links 24 are latched against oscillatory movement by swinging the brace arm into the position of Fig. 9. In addition, the bracket 98 is removed from the'arm-10. Further, the beam 22 is also secured from any oscillatory motion through the medium of a rigid link I58. This link comprises a tubular member I60 having a sleeve I62 at one end, see Fig. 2, loosely mounted on a shaft I64 supported in mounts I66 bolted to the forward ends of the members I0.

One of the spacers 44 is provided with two spaced projections I68 between which a screw I may pass as it is pivoted upwardly about the axis of the shaft I64. The screw is threaded into the end I12 of the tube I60 and is provided with a head I14 which is loosely supported on an unthreaded extent of the screw. Collars I16 are secured to the screw I10 on opposite sides of the head I14 to restrain the screw from relative longitudinal movement, but the screw may be rotated easily.

Two pins I 18 project from the head I14 at right angles to the axis of the screw I10, and the projections I88 are each recessed at I80 to partly embrace one of the pins I18. The pins are rotatably clamped to the projections I68 by fingers I82 each recessed at I84 to partly embrace one of the pins I18, with the two fingers I82 connected together at their rear ends and pivotally connected at I86 with the adjacent spacer 44. Bolts I88 are passed through openings in the fingers I82 and are threaded into the projections I68 to clamp the parts together in the manner of Fig. 9, at which time the fingers and the projections coact as bearings for the pins I18. To the outer end of the screw I10 is fixedly connected a hand wheel I90. Since the screw I10 is restrained from relative longitudinal movement, rotation of the screw imparts pivotal motion to the beam 22 for adjusting the grinding stone 42 to the main bearings 66. Thus the main bearings may be accurately trued, as illustrated in Fig. 9. Ordinary calipers may be employed to take measurements of the main bearings. The screw I10 firmly supports the beam against relative movement in addition to constituting an adjustment for the beam to control the position of the grinding stone with respect to the main bearings.

Having thus described certain embodiments of my invention in detail, it is, of course, understood that I do not desire to limit the scope thereof to the exact details set forth except insofar as those details may be defined in the appended claims.

I claim:

1. In combination with a lathe having a carriage and means for supporting and rotating a crankshaft, oscillating links mounted on said carriage, a beam pivotally connected with said oscillating links intermediate its endsgarotarygririd crankshaft, resilient means acting on 1 said crank pin .for holding said contacting surfaces in engagement with the crank pin to oscillate said links and said 'beam and move said grinding stone in conformity'withthe'travel of the crank pin, a motor mounted on said'beam in a position thereon to pivot'the beam and the grinding elementiaway from the crankpin and operatively connected with said grinding stone, and means acting on said arm and said beam for adjusting thearm relatively to the beam to position the grinding element'in grinding proximity to the crank'pin.

2. The inventiondescribedin claim l wherein means .areprovidedfor bracing saidlinks against oscillation, and means for supporting said beam against pivotal movement and adjusting the same to position the grinding stone in grinding proximity to a main bearing of the crankshaft.

3. In combination with a lathe having a carriage and means for supporting and rotating a crankshaft, a support mounted on said carriage, a beam pivotally mounted on said support, a power driven grinding stone rotatably mounted on said beam, and means acting on said beam to secure the latter against pivotal movement and to adjust the same toward and away from a main bearing on the crankshaft to position the grinding stone in grinding proximity with the main bearing.

4. An attachment for a lathe having means for supporting and rotating a crankshaft, an oscillating support mounted on the lathe rearwardly of the crankshaft, a beam pivoted between its ends to the support with the front portion thereof overlying the crankshaft, a grinding disc mounted on the beam forwardly of the pivot of the beam and having its lower edge contacting with a crank pin of the crankshaft directly over the center of the crank pin, means for rotating the grinding disc mounted upon the beam rearwardly of the pivot of the beam, an arm connected to the beam rearwardly of the grinding disc and extending therefrom in the direction of the crank pin at an angle of 45, the lower end of the arm being provided with a recess open at its upper side and receiving the crank pin with its lower and rear walls in contact with the crank pin, and means carried by the lower end of the arm and contacting with the crank pin to maintain said walls in contact with the crank pin.

5. A lathe attachment as set forth in claim 4, wherein the arm is secured to the beam b means adapting the arm to be adjusted bodily with relation to the grinding disc, and wherein the arm is adjusted and held in adjusted position by means carried by said first means.

6. An attachment for a lathe as recited in claim 4, wherein the arm is provided at its upper end with an extension extending upwardly and for wardly therefrom at right angle thereto, wherein a guide carried by the beam slidably receives the extension of the arm, and wherein an adjusting screw is swivelly mounted on the guide and engaged with the extension of the arm.

7. A lathe attachment as set forth in claim 4, wherein the arm is adjustably secured to the beam for bodily adjustment with relation to the grinding disc, and wherein the means carried by the lower end of the armand contacting with the crank pin comprises a spring p d p 8. In combination with a lathe having acarriage and means for supporting and rotating a crankshaft, an oscillating support mounted on said carriage, a beam pivotally mounted on said support, a power driven grinding element rotatably mounted on said beam, an arm adjustably connected with said beam and having two relatively fixed surfaces contacting with a crank pin of the crankshaft, a spring pressed pin carried by the arm and contacting with said crank pin to hold said surfaces thereagainst to efi'ect the oscillation of said support and said beam and move said grinding element in conformity with the travel of the crank pin, and means acting on said arm and said beam for adjusting the arm relatively to the beam to position the grinding element in grinding proximity to the crank pin.

9. In combination with a lathe having a carriage and means for supporting and rotating a crankshaft to oscillate said support and said beam and move said-grinding element in con-t formity with the travel of the crank pin, means acting on said arm and. said beam for adjusting the arm relatively to:the beam to position thegrinding element in grinding proximity to the, crank pin, means, tohold said support against oscillation, and means for securing the beamagainst pivotal movement on said support and adjust said grinding element, into grinding proximity to a main bearing on the crankshaft.

WILLIA HOWAR MYERS. 

